It is known in marking and coding art to apply a code to an outer case or carton as it moves down a delivery conveyor. An example of this is the application of a barcode to the surface of the case, the barcode being applied by a non-contact print-head mounted in a fixed position on one side of the delivery conveyor. As the case is carried past the print-head by the conveyor, marking is emitted from the print-head to impinge on the surface of the case.
In many instances, the appropriate code must be applied to at least two perpendicular surfaces of the case. For example, the code must be applied to the front and a side of the case. Conventionally, this has necessitated the use of two print-heads arranged on sections of the conveyor that are at right angles, and has also meant that the direction of travel of the conveyor must be turned through 90°.
The provision of two print-heads is expensive as is the need to provide additional conveyor sections. The further conveyor sections also occupy additional factory space and the need to displace the delivery line through 90° also limits the delivery speed.
Attempts have been made to effect coding on perpendicular surfaces using a single print-head. Published International (PCT) Patent Application No. WO 03/102755 describes a system for applying printed information to different surfaces of a package. The system includes a printing applicator which moves relative to the package, the applicator being combined with actuation and feedback means to ensure proper positioning of the printing applicator relative to the package. U.S. Pat. No. 4,745,857 and European Patent No. 1 537 917 describe alternative forms of an apparatus for marking different surfaces of objects such as packages or component parts, using a single print-head. However, in both cases, the print-head is positioned by a robotic arm under computer control.
It will be appreciated that the positioning mechanisms described in the patent references discussed above are expensive and the costs thereof are likely to exceed the cost of providing the conventional two print-head system also described above. Further, each particular application involves programming the positioning mechanisms to operate in the required manner.
It is an object of this invention to provide an apparatus and/or a method which will go at least some way in addressing the aforementioned drawbacks, or which will at least offer a novel and useful alternative.